Directions:
a) list and define all vocabulary from the chapter
b) type at least 4 sample problems with step-by-step directions of how to solve the problem; list the correct answers (if your chapter doesn't have math, there are still problems and concepts we learned.)
c) link at least 3 websites for additional resources to help with studying
d) develop your own LEQ questions for the section - what did you think were the key points we learned?
e) Once your page is done, visit 4 other chapters and answer their LEQ's. (This can be done on a separate piece of paper.)

Vocab-

Pressure- force / area

-units of pressure:
- 1 atm- atmospheres = 760 mmHg = 760 Torr
- 1 atm = 101,325 Pa (pascal) = 101.325 KPa (kilopascal)

Boyle's Law- (P1)(V1) = (P2)(V2)
- constant temperature, constant amount of gas
- pressure changes inversely to volume
Charles' Law- V1/T1 = V2/T2
- Temperature and volume increase proportionally
- Temperature MUSTbe in Kelvin
  - T(k) = T(Celsius) + 273.15
Ideal Gas Law- PV= nRT
- R is the gas constant - used when discussing a SINGLE gas in a NON-CHANGING environment
  - R = PV/ nT= (1 atm)(22.414 L) / (1 mol)(273.15 K)
  - R= (0.082057 x atm) / (mol x K) or (8.314 x KPa)/ (mol x K)
STP- Standard temperature and pressure= 0 degrees Celsius and 1 atm of pressure
- Experiments show that at STP, 1 mol of an Ideal Gas occupies 22.414 L
Combined Gas Law- (P1)(V1) / T1 = (P2)(V2)/ T2
- happens when n and R are constant
Dalton's Law of Partial Pressure = Ptotal= Pa+ Pb
- V and T are CONSTANT
- Pa = (nA)(R)(T) / V and Pb = (nB)(R)(T) / V
- Mole Fraction (X) is the percent of each gas pressure present in the total.
  - XA= nA / (nA + nB) and XB= nB / (nA + nB)
Graham's Law= Rate 1 / Rate 2 = Sqr root of (M2 / M1)
- Rate 1 = faster, lighter gas
- Rate 2 = slower, heavier gas
- Comparing two or more speeds of gases.

Helpful LEQ's:

When do you use each Gas Law?
What are the formulas of each gas law?
What are the units of pressure?
What are the different relationships between pressure and volume in the different gas laws?

Practice Problems:

Boyle's:
- A sample of chlorine gas occupies a volume of 946 mL at a pressure of 726 mmHg. What is the pressure of the gas (in mmHg) if the volume is reduced at a constant temperature to 154 mL?
- (726)(946)= P2(154)
  - Divide each side by 154 to find the figure for P2
  - the answer will be 4460 mL
Charles' :
- A sample of carbon monoxide gas occupies 3.20 L at 125 degrees Celsius. At what temperature will the gas occupy a volume of 1.54 L if the pressure remains the same?
  - Change the temperature to kelvin: 125 + 273.15
  - T2 = V2(T1) / V1 = (1.54)(398.15) / 3.20 = 191.6 Kelvin
Ideal Gas Laws:
- A Balloon contains 2.00 g of He at a pressure of 105 kPa and a temperature of 300 Kelvin. What is the volume of the balloon?
  - PV = nRT therefore V= (nRT) / P
  - Find the moles of He in 2.00 g
  - plug it all in
    - V= (.5)(300)(8.314) / 105
    - V= 11.9 L
Combined:
- a 7.00L Sample of argon gas at 420 Kelvin exerts a pressure of 625 kPa. If the gas is compressed to 1.25 L and the temperature is lowered to 350 Kelvin, what will be the new pressure?
  - P1(V1) / T1 = P2(V2) / T2
  - 625(7.00L) / 420 K = P2(1.25) / 350 K
  - Cross multiply the fractions and solve for P2
  - P2= 2920 kPa
Dalton's:
- A mixture of 1.00 g of H2 and 1.00 g of He is placed in a 1.00l container at 27 degrees C. calculate the partial pressure of each gas and the total pressure.
  - PV= nRT therefore P= nRT / V
  - Convert temp to Kelvin
  - Find the moles of H2, plug it all in:
  - (0.48)(0.0821)(300.15) / 1L = 12.07 atm H2
  - Do the same math for He:
  - (0.25)(0.0821)(300.15) / 1L = 6.16 atm He
  - Add the pressurestogether to get the Ptotal: 18.23 atm
Graham's Law:
What is the molecular weight of a gas which diffuses 1/50 as fast as hydrogen?
Rate1/ rate 2 = sqr root of M2 / M1
1/50 = sqr root of 2.02 / x
Sqr both sides, cross multiply
X= 5050 g/mol

Gas Laws

Vocab-

Helpful LEQ's:

Practice Problems:

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